Coolant leak 2020 Expedition Platinum

[Tom991]

My 2020 Expedition with 60000 miles is going through coolant. The fan came on and was running at super speed. I check the coolant level. The reservoir was empty. I put a half gallon of Motorcraft coolant to get it between min and max. The fan went back to normal speed. Less than a week later same thing. Coolant was low. I don't see any leaks. I borrowed a pressure tester hooked it up after refilling the reservoir. I'd pump but it wouldn't hold and pressure. Still I see no leaks or hear any hissing. I checked the oil. Oil is fine and not milky. I tested the test kit on another car, no problem ai I know it's not the test kit. I don't feel any air escaping out of the cap. Tomorrow I'm going to take the engine cover off the top of the motor so I can see the heater hoses better.

Any suggestion?

Thanks

 

[Fastcar]

Look at your exhaust. I would think that if it was from the hose's it would run down so that you would see it on the ground.

 

[Tom991]

Look at your exhaust. I would think that if it was from the hose's it would run down so that you would see it on the ground.

The exhaust looks fine. No white smoke or the smell of antifreeze. It's funny when I try to pressurize the radiator I see no bubbles in the reservoir. I don't see any indication of a blown head gasket. I guess I could pull the plugs and see if they look super clean.

 

[99WhiteC5Coupe]

My 2020 Expedition with 60000 miles is going through coolant. The fan came on and was running at super speed. I check the coolant level. The reservoir was empty. I put a half gallon of Motorcraft coolant to get it between min and max. The fan went back to normal speed. Less than a week later same thing. Coolant was low. I don't see any leaks. I borrowed a pressure tester hooked it up after refilling the reservoir. I'd pump but it wouldn't hold and pressure. Still I see no leaks or hear any hissing. I checked the oil. Oil is fine and not milky. I tested the test kit on another car, no problem ai I know it's not the test kit. I don't feel any air escaping out of the cap. Tomorrow I'm going to take the engine cover off the top of the motor so I can see the heater hoses better.

Any suggestion?

Thanks

I’d bet your engine water pump is leaking when the engine is running.

 

[Gary Waugh]

If the system is not pressurizing with the test kit, and you are not seeing coolant leak from anywhere, then it would suggest the leak is at a high point and you are just forcing the air trapped at the high point out of the coolant system via the leak. I assume that when you try to pressurize the system the coolant level drops? If yes I would suggest to keep topping up the coolant system and repressurize the system. At some point you will have forced all the air out of the coolant system and coolant will start to appear and give an idea where the leak is. Several people have had leaks in the rear heating radiator, but the coolant pipes go up quite high to get to the rear radiator and are hard to find as the rear coolant system fills with air and like you the testing just forces the air out, which cannot be seen..

 

[TheDoug]

Check for

I’d bet your engine water pump is leaking when the engine is running.

I second this

 

[Tom991]

If the system is not pressurizing with the test kit, and you are not seeing coolant leak from anywhere, then it would suggest the leak is at a high point and you are just forcing the air trapped at the high point out of the coolant system via the leak. I assume that when you try to pressurize the system the coolant level drops? If yes I would suggest to keep topping up the coolant system and repressurize the system. At some point you will have forced all the air out of the coolant system and coolant will start to appear and give an idea where the leak is. Several people have had leaks in the rear heating radiator, but the coolant pipes go up quite high to get to the rear radiator and are hard to find as the rear coolant system fills with air and like you the testing just forces the air out, which cannot be seen..

It turned out that the pressure tester I was using had a defective pump. I got a different one and was able to pressurize the system. Waalaa the leak was in the heater hose near the firewall. I understand this is a common leak prone site for these Ford expeditions with the 3.5 eco-boost in it. It's a poor design the way it's connected. I decided to replace both heater houses instead of having to do the job twice if the other one decides to fail.

Thank you all for your input.

 

[Gary Waugh]

Glad you found it..

 

[ZigZagFred]

My problem was similar. I didn't have a leak, but one of the PLASTIC "Y" heater hose connectors blew out while I was driving on the freeway. Fortunately, I was less than a mile from my house and was able to limp home. If I had been making a long cross-country trip when this happened, it would have been a disaster. The cost savings gained in these heater hoses and connectors have really disappointed me in my beloved Ford company.

 

[Grrumpy]

My problem was similar. I didn't have a leak, but one of the PLASTIC "Y" heater hose connectors blew out while I was driving on the freeway. Fortunately, I was less than a mile from my house and was able to limp home. If I had been making a long cross-country trip when this happened, it would have been a disaster. The cost savings gained in these heater hoses and connectors have really disappointed me in my beloved Ford company.

I don't exactly know what part/post was made but a member posted a replacement "Y" connector was available. Believe it was an aluminum casting......and I think it was at Rock Auto.....
Maybe look into getting one and keep it in the Expy for an emergency.....
Also....google up "Ford Expedition Heater Hose Y Connection" and a bunch of sites come up along with several Y Connector Products....
Dorman 47294.....$25 bucks on Amazon.
SMMS Kit 47238HP.....$19 bucks on Amazon

 

[Tom991]

I don't know why they didn't design a metal manifold and use standard squeeze clamps instead of those clips which are a pain to remove because of the location of the Y pipe

 

[Grrumpy]

I don't know why they didn't design a metal manifold and use standard squeeze clamps instead of those clips which are a pain to remove because of the location of the Y pipe

Plastic piece.....10 cents.
Cast aluminum.....$1 to maybe $2 bucks.
I'll let you figure it out......

 

[GT350driver]

Check for


I second this

I approve the motion to watch the water pump

 

[Tom991]

I approve the motion to watch the water pump

I will be watching the water pump. The water pump is easier to get to than the heater hose Y connectors up against the firewall. If I ever need to replace the water pump should I replace the thermostat at the same time?

 

[spo0587]

Most definitely. I did, when getting the new cam phasers, I did the water pump too since it was growling, and new updated TSTAT with new coolant. So far so good.